Residual-stress determination by single-axis holographic interferometry and hole drilling—Part II: Experiments

Experiments to assess the ability of the holographic/hole-drilling technique to accurately determine uniaxial stresses are described. The experimental data are in the form of optical interference fringe patterns. Different patterns obtained by varying the direction of laser light illuminating a test specimen with respect to the direction of stress are shown. Stresses estimated by the technique are compared with known values in specimens of aluminum alloy 7075-T651 and hardened Type 304L stainless steel.